Title of article :
Numerical analysis of the electrochemical impedance spectra of the cathode of direct methanol fuel cells
Author/Authors :
Chen، نويسنده , , M. and Du، نويسنده , , C.Y. and Yin، نويسنده , , G.P. and Shi، نويسنده , , P.F. and Zhao، نويسنده , , T.S.، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2009
Abstract :
A mathematical model is developed to simulate the electrochemical impedance spectra (EIS) of the cathode of a direct methanol fuel cell (DMFC) based on the electrode kinetics and mass transports. Successful simulation of the impedance spectra confirms the usefulness of the model as a diagnostic tool for interpreting the impedance characteristics of the cathode. Numerically, the capacitive semicircle in the impedance pattern is ascribed to the charge transfer process and the inductive semicircle is mainly due to the CO adsorption relaxation. Results show that the impedance pattern is strongly dependent on the electrode potential, which can be used as a criterion for judging the relative effect of the methanol permeation on the cathode. Another capacitive semicircle appears and the charge transfer resistance is changed when the oxygen transport is limited. The effects of the methanol permeation on the impedance pattern are also delineated, indicating that the methanol permeation often leads to larger oxygen transport impedance and the charge transfer resistance of the DMFC cathode depends on the methanol permeation rate.
Keywords :
DMFC , cathode , Electrochemical impedance spectra , Mathematical model
Journal title :
International Journal of Hydrogen Energy
Journal title :
International Journal of Hydrogen Energy